Amtrak announced yesterday that it would increase fares on most of its passenger routes on Oct. 30 and cancel more than two dozen trains a day, almost all of them in the busy Washington-to-Boston corridor.

Amtrak spokesmen said the decisions were made in a move to erase the system's $50-million-a-year operating deficit.

Fares on most Amtrak trains will go up 2.5 per cent. A few busy routes will post 5 per cent fare increases while a few fare schedules will remain unchanged.

At the same time, the system said it would reduce service on four routesM three of them in to Washington.

An average of 22 trains a day will be taken off the Washington-Boston corridor, Amtrak's most heavily traveled route. Several weekend Metroliners, two other Washington-to-New York trains (one Friday, one Sunday) and a number of shorter runswill be ended.

The Shenandoah, from Washington to Cincinnati via Parkersburg, W. Va., will run only four instead of the present seven days a week, as will the Hilltopper, from Washington to Catletsburg, Ky.

The Chicago-Milwaukee Turboliner will be cut back from four round-trips a day to three, and an additional train which operated only on Sundays will be eliminated.

Previously announced plans to expand service along the East Coast to Florida will be curtailed.

Amtrak said the lates service cut-backs and others in recent weeks are intended to save an estimated $28 million.

More than 1,000 Amtrak employees will be laid off when the cancellations become effective and passenger service to 26 states is reduced, an Amtrak spokesman said.

No estimate of additional revenue from fare increases was available, but the spokesman said it would still not be enough to close the budget gap.

"We think this will be the last of the of the frequently reductions, but not te last of the cost-cutting measures," he said. Services - such as snack bars and lounge cars - will probably be reduced on some trains and some stations may closed or operated for fewer hours.

Yesterday's annoucement about fare increases and service cuts was the latest in a series of budget-dictated moves that have taken Amtrak further and further from its original goal.

Whe Congress chartered the National Railroad Passenger Corp., it was to provide a comprehensive, convenient, low-cost system of railroad transportation. The purpose was to rebuild the passenger routes that had been abandoned by private rail lines.

But many new trains launched by Amtrak have since been dropped and fares have climbed steadily. The most recent increase was a 3 to 5 per cent rise only three months ago.

On, Amtrak's most heavily traveled route, from Washington to New York, fares have climbed from $13 to $20 and will go up another 50 cents on Oct. 30.

The latest fare increases will be pegged at five cents on fares of $1 to $3.20 cents on fares from $3 to $5, 25 cents on fares from $5 to $15, and a flat 2.5 per cent above that.

The Washington-New York metro-liner fare, now $25 one-way, will be increased by about 2.5 per cent, but the exact increase has not been determined. (KEY OFF)(KEYWORD)mtral said a handful of trains that have had strong ridership gains will get 5 per cent increases. Those trains were not identified yesterday, nor was another small group on which fares will not be raised.

Since June 1, Amtrak has taken some trains off routes between St. Bakersfield, Calif.; New York and Savannah, and between Chicago and Seattle.

As of Oct. 30, these trains serving Washington will be cancelled:

Metroliner 110, Wasshington to New York, 11 a.m. Saturday; Metroliner 114, Washington-New York, 1 p.m. Saturday; Metroliner 104,Washington-New York, 8 a.m. Sunday; Metroliner 106, Washington-New York, 9 a.m. Sunday.

Metroliner 105, New York-Washington, 8:30 a.m. Sunday; Metroliner 107, New york-Washington, 9:30 a.m. Sunday; Metroliner 109, New York-Washington, 10:30 a.m. Sunday; Metroliner 113, New York-Washington, 12:30 p.m. Saturday.

Train 166, Washington-New York, 8:05 p.m. Friday and Saturdays.

The Hilltopper, from Washington to Catlettsburg, ky., will run only Thursday through Sunday and from Catlettsburg to Washington only Saturday through Tuesday.

The Shenandcah from Washington to Cincinnati will run only Thursday through Sunday and from Cincinnati to Washington will run only Friday throught Monday. This change requires approval of the Department of Transportation.

Other Northeast corridor trains to be dropped include:

New York-Philadelphia, Trains to be cropped York 6:35 a.m. Monday-Friday, 213 leaving New Yord 2 p.m. daily; 227 leaving New York 7:05 p.m. daily; 250 leaving Philadelphia 5:45 a.m. Monday-Saturday; 168 leaving philadelphia 7:15 a.m. daily; 204 leaving Philadelphia 9 a.m. daily; 220 leaving Philadelphia 5 p.m., Sunday-Friday; 222 leaving Philadelphia 6 p.m. Sunday-Friday.

New York-Harrisburg, Pa., Train 42 leaving.